I've developed a hot spot that is just a step away from becoming a saddle sore on my left side, and a 60 mile ride coming up this week. This has only occurred after I upped my mileage and specifically first showed up after a ride that included a 45 minute 2200' climb. Today was a 45 mile ride of rolling hills and smaller climbs, but the little beast was angrier than ever by the time I was done. I've been consistent in lubing up the chamois with Chamois Butt'r, and that's what probably has held it at bay thus far. So:

1) I'm considering, for the long ride, slapping a large patch of moleskin over the reddened/roughened area to stave off an uncomfortable 3 hours. I've used this for hot spots on the feet for marathon training, but don't know if this is the right answer for the sit bone. Anyone tried this? Other proven alternatives?

2) From what I've pulled up off the interweb, since this is happening only on one side, it may be either a saddle fit issue or, more likely, an uneven stroke. When I had my fitting the fitter did indicate after watching me that I had a nice even stroke on the right side but a much more pronounced downstroke on the left, so it sounds like some single leg drills may be in order. Opinions?

More then likely it has nothing to do with your pedal stroke, but commonly this is related to a shorter stroke on one side. This is from either a leg length discrepancy (which is very common), or a function length difference (shorter hamstring for example on the left side in your case).

Try lowering you saddle ever so slightly. That usually helps a lot.

Also, try a different detergent on your cycling shorts. It could very well be that the detergent you are using left a very small amount of residue, which can cause a small infection (which is exactly what a saddle sore is, an infected abrasive sore).

I doubt mole skin is the solution though... keep it clean and dry for now and stay off the bike for a few days to let it heal. A bad saddle sore can keep you off the bike for the remainder of the season... yes, they can get that bad.